First transaction in a block

Question

What is this first transaction the block that is returned via OP_RETURN? Is this a transaction created by the mining node or is it just a creation transaction to create the block?

Answer 1

The first transaction is the coinbase transaction, as a reward to the miner.

Answer 2

The first transaction is called the coinbase transaction, and it serves two purposes:

• In chains with a miner reward system, it indicates the address of the miner who collects that reward (this is exactly like bitcoin).
• In chains with mining based on permissions, it contains the signature proving which miner address generated that block (this is a MultiChain addition): https://www.multichain.com/developers/mining-block-signatures/